1. Field of the Invention
The present invention relates to apparatus for selectively magnetizing and demagnetizing a hand tool, such as a screwdriver, a nutdriver, or the like. More particularly, the present invention relates to a portable device in the form of an enclosure, the enclosure having a pair of respective openings to permit the insertion thereinto of a tool that is either to be magnetized or to be demagnetized.
2. Description of the Related Art
It is often desirable to provide a hand tool, such as a screwdriver, a nutdriver, or the like, with a magnetized end for magnetically retaining a screw or nut in order to facilitate holding and orientation of the screw or nut as it is being applied to fasten parts together, or as it is being removed from the parts. Similarly, there also are times when it is desirable that the tip of screwdriver or a nutdriver not be magnetized, for one reason or another.
Various arrangements have been proposed to magnetize and demagnetize small hand tools utilizing various forms of magnetic electrical circuits. For example, in U.S. Pat. No. 4,160,283, which issued Jul. 3, 1979, to Ralph W. Adams, there is disclosed a magnetizing and demagnetizing tool in which a magnetizable core made from iron is provided within an encircling coil that is connected to a source of alternating current through a normally open switch that is closed to complete an electrical circuit. The device includes various mechanical elements that are movable to cause the opening and closing of a pair of contacts.
Other devices for magnetizing or demagnetizing articles are shown in U.S. Pat. Nos. 2,125,628; 3,346,778; 4,370,693; and 4,591,943.
Although the previously disclosed magnetizing devices are effective for their intended purpose, they involve complex electrical circuits or movable mechanical elements that require maintenance, repair, and adjustment, and that also result in higher weight, rendering use of such devices less convenient.
It is an object of the present invention to overcome the shortcomings of the prior art devices.
It is another object of the present invention to provide in a compact enclosure both a magnetizing and a demagnetizing circuit for conveniently magnetizing or demagnetizing small tools, and the like.
It is a still further object of the present invention to provide a relatively small, hand-held magnetizing and demagnetizing device that is of light weight and is easy to use.